Affiliation:
1. Aramco Rowan Offshore Drilling Co. KFUPM-Ph.D. Researcher
Abstract
Abstract
Drilling operations take place in an environment where high and low pressures are challenges. Both can cause delays, increased expenses, and even failure if they occur unexpectedly. Operators are increasingly equipping themselves against the repercussions of pressure-related surprises by employing strategies that are distinct from those previously employed. Managed pressure drilling (MPD) is one such break from tradition. The drilling margin, also known as the pore-pressure-fracture gradient window, is the pressure range between pore pressure and fracture formation pressure. Operators must set casing and begin drilling the following, smaller hole size if the equivalent circulation density (ECD) goes outside these boundaries at any stage. Overbalanced drilling (OBD) is the process of maintaining a borehole pressure that is higher than the pore pressure gradient.
Drilling is challenging in some operations due to the restricted operating window between pore pressure and fracture pressure. An oil field in North Africa is the subject of a feasibility study for controlled pressure drilling. Mud returns were lost while drilling in an unconsolidated formation in prior wells drilled in this field. This project effort solves this issue by applying surface back pressure to Managed Pressure Drilling technology in this field. The methodology used in this study is based on employing a real-time model to optimize (ECD) values and a drilling simulator to compare drilling operation pressures. To compare the pressures with the required back pressure, the model estimates the annular pressure drop and corresponding circulation density.
The goal of this project is to employ Managed Pressure Drilling calculations to drill the well, optimize the mud weights used to drill the well, reduce the number of casing strings, and avoid losing drilling fluid. As a result of this technique, the MPD optimization will be used to drill the well in a safer and more cost-effective manner while avoiding drilling problems, lowering the Non-Productive Time (NPT).